ANAPHYLAXIS IN A MILK-ALLERGIC CHILD FOLLOWING INGESTION OF LEMON SORBET CONTAINING TRACE QUANTITIES OF MILK

Although allergic persons can react to foods containing trace quantiti es of unlabeled or unintended food allergens, there are few data avail able on the quantities of these allergens required to evoke allergic s ymptoms. We report a milk-allergic 3-year-old boy who experienced thro at itching, facial angioedema, and vomiting within 20 min of ingesting 4 to 6 oz (ca. 113.4 to 170.1 g) of lemon sorbet. Subsequent analysis of two sorbet samples provided by the parents and a third sample purc hased locally by the investigators revealed trace quantities of milk a llergens, whey protein (8.8 mu g/ml), or lactose (200 ppm). The quanti ty of whey protein ingested was estimated to be 120 to 180 mu g (equiv alent to 23 to 24 mu l of milk). All three sorbet samples had been man ufactured in the same plant within a Lt-month period; the equipment us ed to produce and package the sorbet was also used to produce and pack age ice cream. No milk allergen or whey protein was detected in 38 oth er marketplace sorbet samples submitted by the manufacturer for testin g. We concluded that trace quantities of whey proteins (<200 mu g) can elicit systemic reactions in exquisitely milk-allergic individuals. S uch individuals should avoid eating frozen desserts prepared using equ ipment also used for producing or packaging ice cream, unless manufact urers can demonstrate unequivocally that their cleaning practices are sufficient to prevent milk contamination. Adequate tests are not curre ntly available to food manufacturers but are under development.